China DOS Union

Ask the moderator, what are the parameters of COMMAND.COM? Could you please explain them in detail? There is such a sentence in a batch file: c:\command.com /c wt.exe, what does it mean?

Here are several parameters of command.com, from Cai Xuan's "Unpublished DOS Parameters" article.

1. COMMAND /F (applicable to MS-DOS 6.00 and above)

COMMAND. COM /F can automatically help you choose one to answer when the system has an error prompt "Abort, Retry, Fail". For example, when using the DIR A: command without a floppy disk in the floppy drive, the system will automatically make several retries. If it still doesn't work, it will choose Fail and exit.

This parameter can run in the DOS window of Windows 95/98, and can also be used with the shell command in config. sys, such as: shell=c:\command.com c:\ /e:512 /p /f.

2. COMMAND /Z (applicable to MS-DOS 7.00 and above)

COMMAND. COM /Z displays the error level number (ERRORLEVEL) when the command execution is completed. Many BAT files perform operations such as selection through ERRORLEVEL. After this parameter is loaded, the error number of all executed commands is automatically displayed at the end. For example:

Microsoft(R) Windows 98(C)Copyright Microsoft Corp 1981-1998.Return code (ERRORLEVEL): 0WARNING: Reloaded COMMAND.COM transient

This parameter can run in the DOS window of Windows 95/98, and can also be used with the shell command in config. sys, such as: shell=c:\command.com c:\ /e:512 /p /z.

There are also undocumented parameters of COMMAND.COM, such as /T, /D, etc.